1. Field of the Invention
This invention relates to electrosurgery and in particular an electrosurgical method and apparatus for coagulating by fulguration.
2. Discussion of the Prior Art
Electrosurgical coagulation by fulguration consists of the establishment of electrical discharges to body tissue with bursts of radio-frequency energy. It is used to dehydrate, shrink, kill, or char the tissue. This is most often to stop bleeding and oozing, or to otherwise seal the tissue. Conventional fulguration techniques are complicated by the following:
1. Very high voltages are required to start and maintain the high crest factor sparking needed for effective fulguration. Few solid state electrosurgical generator systems can provide the output parameters needed for truly satisfactory performance. Sparks are typically short and hard to start and control.
2. With high voltage and crest factor, as provided by conventional generators, the precise control of the fulguration site is impossible due to the "arc" nature of the discharge. The spark does not issue from the point of the electrode in the direction indicated, but arcs from the side of the point in a curved trajectory to nearby flesh. The spark wanders increasingly with greater spark length. Fulguration at the bottom of a hole or crevice is especially difficult to achieve.
3. Should the electrode accidentally touch the tissue, the partially dehydrated tissue can often adhere to the hot electrode and be inadvertently ripped away creating unnecessary complications. In addition to surgical complications, such sticking fouls the electrode such that it must be scraped clean before continuing the operation.
4. Conventional fulguration systems cannot be used to quickly treat large areas of bleeding or oozing flesh.
5. Considerable volumes of dense unpleasant smoke and fumes are produced.